JPS63214993A - Attaching structure for performance information detector in automatic performance piano - Google Patents

Abstract

PURPOSE:To completely require no wiring operation of an optical fiber, a cord or the like by mutually opposing a first printed board on which a photointerrupter is attached and a second printed board on which an electric circuit for processing a detecting signal from the photointerrupter is formed and connecting by a pin. CONSTITUTION:The first and the second printed boards 41, 46 formed respectively to the long size are electrically and mechanically connected by the pin 48, the many photointerrupters 42 are disposed in parallel on the first printed board 41 correspondingly to a respective action mechanisms and the electric circuit for processing electrically the detecting signal from the respective photointerrupters 42 is formed on the second printed board 46. Thereby, the cord, the optical fiber and the wiring operation thereof are not required to remarkably make an assembling operation easy, considerably reduce a production cost and improve a productivity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a mounting structure for a performance information detection device in a player piano, which is designed to reduce costs and improve assembly workability.

[Conventional technology]

A performance information detection device for a player piano detects the speed at which the hammer strikes the string, or the strength (volume) of the string, during recording. Generally, a non-contact type detection device equipped with a light-emitting element and a light-receiving element is used. A light-shielding plate is attached to the action mechanism corresponding to this detection device, so that the light emitted from the light-emitting element passes through the light-shielding plate when a string is struck. The performance information detected by the performance information detection device is subjected to signal processing by an electric circuit, then sent to a data coder and recorded, and is used as a key drive signal during playback.

[Problem that the invention seeks to solve]

Incidentally, an important issue is where to place a printed circuit board on which a circuit for processing a detection signal from such a detection device is printed and wired. For example, if it is installed in a location other than the action mechanism, the distance to the detection device will be longer, resulting in longer optical fibers, cords, etc., making wiring work troublesome and increasing manufacturing costs. The connector must be removed, which is extremely inconvenient. Furthermore, if the upper front panel that makes up the cabinet is removed, it will not be able to be mounted in a visible place, impairing the integrity of the piano.

Therefore, as a method to solve such problems, for example, Japanese Utility Model Application Publication No. 1983-46594 (Utility Application No. 59-13139) is proposed.
As shown in No. 1), it is known that the printed circuit board for the senna is placed in the space between the strings and the center rail in the treble section where the damper mechanism is not attached, but this has a very low tone. The wiring of optical fibers, cords, etc. for the detection device placed on the side becomes extremely long, making the work cumbersome and making it difficult to reduce costs.

[Means for solving problems]

The mounting structure for a performance information detection device in a player piano according to the present invention has been made to solve the above-mentioned problems, and includes first and second printed circuit boards each formed in a long shape and facing each other. are arranged in correspondence with each action mechanism, and a number of photointerrupters each having a light emitting element and a light receiving element and detecting string hitting information are arranged in parallel on the first printed circuit board so as to correspond to each action mechanism. , an electric circuit for processing detection signals from each of the photointerrupters is formed on a second printed circuit board, the first and second printed circuit boards are electrically and mechanically coupled by pins, and both printed circuit boards are connected together. It is configured such that it is divided at the portion where it still contacts the action placket, and adjacent divided boards are electrically connected to each other by a connecting means.

[Effect]

In this invention, a first printed circuit board on which a photointerrupter is attached and a second printed circuit board on which an electric circuit for processing a detection signal from the photointerrupter is formed are formed into elongated shapes and are opposed to each other. Since they are electrically and mechanically coupled using pins, there is no need for any wiring work such as optical fibers or cords.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a side sectional view of an action mechanism section showing an embodiment of the present invention applied to an upright player piano, FIG. 2 is a front page view showing the mounting structure of a photointerrupter to a printed circuit board, and FIG. FIG. 3 is a bottom view of the expansion mounting structure, FIG. 4 is a perspective view of a main part of the mounting structure, and FIG. 5 is a perspective view of a main part of a case in which the mounting structure is housed. In FIG. 1, reference numeral 1 denotes a well-known upright action mechanism that operates in conjunction with keys 3 arranged corresponding to strings 2 of each pitch, and one end of this action mechanism 1 is connected to a center rail 4. 7 The key 3 is rotatably supported vertically via the range 5.
A wippen T is pushed up and rotated by a capstan 6 implanted on the upper surface of the rear end, and a wippen T is disposed above the wippen T via seven ranges 8 so as to be freely rotatable in the front and back direction and counterclockwise by a spring 9. A jack 10 in the form of an abbreviated character, which has a return habit of A bat 12, a catcher 14 attached to the bat 12 via a catcher shank 13, and a bat 1
2, a hammer rail 1B that locks the hammer 15 at the initial position, and the catcher 1.
Pack check wire 1 to the Wippen 7 corresponding to 4.
7, a pack check 18 attached through the wippen T, and a prydle tape 20 connecting the prydle wire 19 planted in the wippen T and the catcher shank 13.
, a regulating button 22 and the like arranged above the small jack 10A of the jack 10, and a key 3.
With the key press operation, the wippen T is pushed up and rotated by the capstan 6, and the jack 10 rises accordingly and the butt 12 is pushed up, and the hammer 15, which rotates together with the nuclear butt 12, hits the No. 1 hammer. It is configured to strike the corresponding string 2.

The jack 10 has a small jack of 10A during the ascent.
However, since the wippen 7 still continues to rotate upward, it rotates clockwise against the spring 9 using the corresponding contact part as a rotation fulcrum. and temporarily escapes from the lower part of the bat 12. Then, when the jack 10 is released from the legge-eleching button 22 as the wippen T rotates and descends after the string-strike operation by the hammer 15, the jack 10 returns to rotation by the force of the spring 9, and the upper end of the jack 10 returns to the lower part of the butt 12. By pushing it in, the next string-striking operation is made possible.

The hammer 15 is composed of a hammer shank 23, a hammer wood 24, and a hammer felt 25.

The center rail 4 has screws attached to the rear surface of a plurality (3 to 5) of action plackets 27 that are erected at appropriate intervals on the shelf board 2B in the direction in which the strings 2 are arranged (direction perpendicular to the page). By being fixed, it extends commonly to all strings 2 and holds all action mechanisms 1. Further, a damper mechanism 28 is disposed on the center rail 4 and operates in conjunction with the action mechanism 1 during a string-striking operation. The damper mechanism 28 presses the normal value 2 to prevent its free vibration and releases the string 2 when the string is struck.The damper mechanism 28 is arranged so that the middle part is rotatable in the front and back direction on the center rail 4 via the flange 29. A damper lever 31 is provided that extends in the vertical direction, a damper 33 is attached to the upper end of the damper lever 31 via a damper wire 32 and presses the normal value 2, and a damper 33 is installed on the upper surface of the pivot point side of the quill pen T. It is comprised of a damper spoon 35 and the like that presses the lower end of the damper lever 31 when the wippen 7 is rotated upward and rotates the lever clockwise against the spring 34. A damper rail 3B for regulating the rotation of the damper lever 31 is disposed at the upper end of the rear surface of the action placket 2T, corresponding to the damper wire 32, and a performance information detecting device 4, which constitutes the gist of the present invention.
0 is placed.

The performance information detection device 40 constitutes a string-striking information sensor that detects the string-striking intensity (volume) by the hammer 1S, and as shown in FIGS. A large number of photointerrupters 42 are arranged in parallel to correspond to each action mechanism 1 at the bottom of a first printed circuit board 41 formed in a long shape so as to extend in common, and a plurality of photointerrupters 42 corresponding to the photointerrupters 41 are provided. and a light shielding plate 43 attached to the hammer shank 23 of each action mechanism 1.

The photointerrupter 42 is formed into a concave shape and has a recess 44 into which the light shielding plate 43 is inserted when a string is struck, and a light emitting element 45 and a light receiving element (not shown) that face each other with the recess 44 in between. ) are provided. In this case, since the strength of string striking by the hammer 15 is proportional to its speed, the photo interrupter 42 is connected to each action mechanism 1.
Two photointerrupters (42m, 42b) are arranged side by side in the front and back direction, and these photointerrupters 42, 42b
The time during which the light shielding plate 43 passes is detected.

That is, each of the photointerrupters 42m and 42b normally sends out a high-level output signal so that the light emitted from the light emitting element 45 cannot be received by the light receiving element, and when a string is struck, the light shielding plate 43 first detects the front side photo. When entering the recess 44 of the interrupter 42m and blocking the light from the light emitting element 45 of the interrupter 42m, the output signal of the interrupter 42m changes from high level to low level and starts counting pulses,
Next, the light shielding plate 43 is connected to the photointerrupter 42b on the rear side.
enters the recess 44 of the interrupter 42b and blocks the light from the light emitting element 45 of the interrupter 42b, and when the output signal of the interrupter 42b changes from a high level to a low level, the counting of pulses is stopped, and during this period the pulse count is stopped. Light shielding plate 4 depending on the number of pulses
This is to detect the passage time of 3. In this case, when the number of pulses is small, the time taken to pass through the light shielding plate 43 is short and the string striking strength is high, and when the number of pulses is large, the time taken to pass through the light shielding plate 43 is long and the string striking strength is low.

A second printed circuit board 46 is disposed above the first printed circuit board 41, facing substantially parallel thereto, and electrically and mechanically coupled to the first printed circuit board 41 through a number of pins 48. . This second printed circuit board 46
Like the printed circuit board 41, it is formed in a long shape and extends commonly to all the action mechanisms 1, and an electric circuit for processing detection signals from each of the photointerrupters 42 is formed. And a photo interrupter 42,
The first and second printed circuit boards fl, 48 are housed in a case 50 formed into a rectangular tube shape, and this case 50
is fixed below the damper rail 36 on the rear surface of the action placket 27. A number of slits 51 are provided in the lower half of the case 50 for each of the photointerrupters 42.
is formed corresponding to the recess 44 of the light shielding plate 43.
It allows entry inside.

In this case, the attachment position of the case 50 to the action mechanism 1 in the front-rear direction is determined in relation to the light-shielding plate 43 immediately after the string is struck, so that the rear end of the action placket 27 is located at the younger side, and therefore , the case 50 and the first. The second printed circuit boards 41 and 46 are divided at the portions that contact the action bracket 27, and nine adjacent divided boards are connected to each other by connecting means 53 such as lead wires, jumper wires, and flexible printed circuit boards. . One end of a cord 54 is connected to one end of the first and second printed circuit boards 41, 46, and the other end of the cord 54 is connected to a data cord (not shown).

〔Effect of the invention〕

As described above, the mounting structure of the performance information detection device in the automatic performance piano according to the present invention includes electrically and mechanically connecting the first and second printed circuit boards, each formed in a long shape, with pins. A large number of photointerrupters are arranged in parallel on the first printed circuit board corresponding to each action mechanism, and an electric circuit for electrically processing detection signals from each of the photointerrupters is formed on the second printed circuit board. Because of this structure, there is no need for cords, optical fibers, etc. and their wiring work, making the assembly work extremely easy, and making it possible to significantly reduce manufacturing costs and improve productivity, and the effects are often great. Furthermore, since the printed circuit board is divided at the portion that contacts the action bracket, the bracket does not get in the way and can be reliably placed at a desired position.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of an action mechanism section showing an embodiment of the present invention applied to an upright player piano, FIG. 2 is a front view showing a mounting structure of a photointerrupter to a printed circuit board, and FIG. Figure 4 is a perspective view of the main parts of the mounting structure; Figure 5 is a perspective view of the main parts of the mounting structure housed in a case. DESCRIPTION OF SYMBOLS 1... Action mechanism, 23... Hammer shank, 2T-@φ action placket, 40... Performance information detection device, 41... First printed circuit board, 42, 42m, 42b ...7 Oto interrupter, 43... Light shielding plate, 44 @ @ @ @ recessed part,
45-Fist...Light emitting element, 46--Second printed circuit board, 53-@...Connection means.

Claims (1)

[Claims] A first printed circuit board formed in an elongated shape is disposed so as to correspond to each action mechanism, and a number of photointerrupters each having a light emitting element and a light receiving element facing each other and detecting string hitting information are connected to the first printed circuit board. A second printed circuit board formed in an elongated shape is arranged in parallel to correspond to each of the action mechanisms on the printed circuit board to form an electric circuit for processing detection signals from each of the photointerrupters. The first and second printed circuit boards are electrically and mechanically connected by pins, and the first and second printed circuit boards are connected to the action bracket. 1. A mounting structure for a performance information detection device in a player piano, characterized in that the divided substrates are divided at an abutting portion and adjacent divided substrates are electrically connected to each other by a connecting means.